Timing device



July 19, 1960 A. F. WINSLOW TIMING DEVICE me March 31, 1944 INVENTOIR ARTHUR F: Wl/VSLOW PR/MER- ATTORNEY United States Patent Ofice' TIMING DEVICE Arthur F. Winslow, Scofia, N.Y., assignor to the United States of America as represented by the Secretary of the Navy Filed Mar. 31, 1944, Ser. No. 529,008

9 Claims. (Cl. 102-16) This invention relates to timing devices, particularly for electrical circuits of the varieties employed in con trolling the action-f many items of underwater explosive ordnance. The invention incorporates novel means adapted to coact with the water in which such an item of underwater ordnance is immersed, to initiate the action which results in firing of the explosive charge, as well as to interpose a predetermined delay between the time of immersion and the time of arming.

An important object of the invention is to provide such a time delay and controlling devicewhich is of extremely simple character, which incorporates no moving parts, and which is of such rugged character that reliable operation is virtually insured, even though the device be subjected to severe mechanical abuse prior to being called upon to function.

Another object of the invention is to provide such a device so arranged that it normally short circuits the electrical energizing apparatus which functions to control the detonation of the item of ordnance, the detonating means being thereby rendered entirely inefiective and safe, while the breaking of the short circuit at the end of the timed interval arms the device, permitting the detonating means to function in the normal manner.

Other objects will be apparent from the following description taken in conjunction with the drawing forming a part hereof.

The single figure of drawing constitutes a vertical substantially central cross section of a timing device con structed in accordance with my present invention, other electrically connected elements being illustrated diagrammatically.

Referring now to the drawing, the body of my improved timing device comprises a substantially cylindrical casing 1, preferably formed of insulating material which is resistant both to the passage of heat and electricity and provided with a firmly attached cover 2 perforated at 3 to admitwater to the interior of the housing assembly thus formed. Contained within the casing is a quantity of a material adapted to generate heat when contacted by water. A suitable material for this purpose is sodium monoxide, which decomposes exothermically in water. A fusible link 5 extends across the casing 1 and through a portion of the sodium monoxide 4.

As indicated in the drawing, the timing device is shun-ted across the battery 8, the battery being connected.

toand adapted to fire the electrically operable primer 10, although such firing is prevented so long as the link 5 remains intact and thus short circuits the battery.

If desired, the battery 8 may be of the sea battery variety, so that it becomes operative when the item of ordnance is immersed in the sea, while at the same time the Patented July 19, 1960 timing device begins to generate heat due to the entrance of sea water through the aperture 3. The time required to sever the link constitutes the arming period. An additional controlling or fuzing device may be incorporated in the circuit between the battery and the primer 10, as indicated at F. It will be evident that after the link 5 is broken, the item of'ordnance will be detonated upon actuation of element F.

It will also be understood that the time required to fuze the link 5 and thus arm the item of ordnance depends primarily upon the diameter of the link 5, and that links of different diameters may be used to vary the arming time as may be desired.

I claim:

1. A timing device for an underwater item of ordnance comprising a housing, means for admitting sea Water into said housing, a quantity of material in such housing which generates heat when contacted by such water, a fusible link of electrical conducting material in said housing, a first electrical circuit including said fusible link, a second electrical circuit in parallel with said first circuit and including firing means for. said item of ordnance, a source of electrical power for said circuits, said first circuit being a low resistance shunt for said source of electrical power, said generated heat fusing said link and interrupting said first circuit whereby said firing means in said second circuit is actuated.

2. A timing device as defined in claim 1 in which said housing is formedof material resistant to the passage of both heat and electricity.

3. A timing device as defined in claim 1 in which said heat generating material decomposes exothermically when contacted by water.

4. A timing device as defined in claim 1 in which said heat generating material comprises sodium monoxide.

5. In a timing device for an underwater item of ordnance, a housing, means for admitting sea water into said housing, a quantity of material in said housing which generates heat when contacted by such water, a fusible link of electrical conducting material in said housing, an

electrical circuit including said fusible link, a source of electrical power for said electrical circuit, said generated heat fusing said link and interrupting said circuit.

6. The structure defined in claim 5 wherein said housing is formed of material resistant to the passage of both heat and electricity.

7. The structure defined in claim 5 wherein said heat generating material comprises sodium monoxide.

8. For use in a timing device for underwater ordnance including an electrical circuit and a source of power therefor, the combination comprising a housing, said housing being formed of material resistant to the passage of both heat and electricity, means for admitting sea water into said housing, a fusible link of electrical conducting material in said housing, and material in said housing which generates heat when contacted by water.

9. The structure defined in claim 8 wherein said heat generating material is sodium monoxide.

References Cited in the file of this patent V UNITED STATES PATENTS 693,718 Julig Feb. 18, 1902 910,943 McCombie Ian. 26, 1909 923,646 Grott June 1, 1909 1,755,797 Schwenke Apr. 22, 1930 

